Improve handling of requests without whitespace
Improve handling of requests without whitespace

Initially, whitespace was left optional between a request's name and its
arguments to stay compatible with classical Troff. This ended up causing
more problems than it solved, as long macro names became mishighlighted:

    .space -> .sp ace
    .init  -> .in it
    .check -> .ch eck

This has been fixed, as most files in the wild would've been written for
a modern implementation (GNU/Heirloom). The original issue isn't ignored
though; requests with numbers attached are matched so lines like ".ps15"
are highlighted correctly in older files.

Alhadis/language-roff,Alhadis/language-roff